Chemical protective garments have traditionally consisted of coverall concepts or stand-alone concepts. The former is an overgarment designed to be worn over existing operational clothing. It consists of an outer shell layer and a chemical adsorptive layer. The adsorbing component of the chemical adsorptive layer typically consists of an activated carbon which acts to filter out toxic chemicals from the air that passes through it. These coverall concepts are typically bulky and not tailored because of the requirement to fit over other clothing. There is generally a significant volume of air space within these protective systems, both between the protective coverall and the operational clothing underneath, and between the operational clothing and the body. A stand-alone protective garment is a lighter version of the protective coverall. It is typically only worn over boxer shorts and a T-shirt. The stand-alone protective garment consists of a liquid repellent outer shell layer, a chemical vapour adsorptive layer and a skin comfort layer.
The bulky and loose fitting nature of the coverall and standalone chemical protective garments tend to promote a bellows effect when the garment is worn, which is the movement of the fabric layer relative to the body during active wear. The bellowing effect acts much like a pump, drawing air that is potentially contaminated with harmful chemicals, inside conventional protective garments mainly through closures (hood/respirator interface, wrists, ankles and zippers etc), but also through the fabric itself. Once the contaminated air breaches the protective coverall or stand-alone garment and penetrates inside, it can be absorbed by the skin with possible health risks to the individual if the exposure level exceeds the allowable dose.
Accordingly, there is a long-felt need to have a thin, stretchable chemical vapour protective garment which allows the user to wear it next-to-skin and beneath other operational clothing to protect the skin from direct exposure to unfiltered, air containing harmful chemicals.
The concept of skin tight protective suit for noxious chemicals was disclosed in U.S. Pat. No. 5,017,424 (Farnworth et al.), which is incorporated herein by reference. Farnworth et al. discloses a composite material resistant to passage therethrough of noxious substances. The composite material is comprised of a first layer impermeable to water and particulate materials but permeable to vapours that takes the form of a film; a second layer of vapour permeable stretch fabric material; and a third layer disposed between the first and second layer and consisting of vapour permeable stretchable fabric material containing a particulate adsorbent material to remove the noxious vapours. However, protective suits which require multiple layers of fabric means that they are more suitable to be worn as the only garment. Only in non-heat stress conditions can they be worn as an undergarment. This poses a practical problem in arduous, real life operations where special operating clothing are required to be worn over the protective suit.
It is therefore desirable to have chemical vapour protective suits for wearing next-to-skin as undergarments which allow the users to wear their own specialized operational clothing over top, such as a bomb disposal overall, special forces combats or coveralls, fighter jet pilot coveralls, first responder protective gear, etc.